Barrel sanding machine



Dec. 19, 193

M. ELSKAMP 1,939,674

BARREL SANDING MACHINE Filed March 11, 1933 4 Sheets-Sheet 2 1933- M.ELSKAMP BARREL SANDING MACHINE Filed March 11, 1933 4 Sheets-Sheet 3 A!@I/FX/ENTOR BY W m ATTORNEYS Dec. 19, 1933. L M, ELSKAMP 1,939,674

BARREL SANDING MACHINE Filed March 11, 1953 4 Sheets-Sheet 4 ATTORNEYSPatented Dec. 19, 1933 UNITED STATES BARREL SANDING MACHINE MartinElskamp, Buifalo, N. Y., assignor to E. & B. Holmes Machinery 00.,Buffalo, N. Y., a corporation of New York Application March 11 9 Claims.

This invention relates to a machine for sanding or polishing theexterior of barrels having a bilged or bulging center part and narrowreduced or tapering ends on opposite sides of this bilge, such barrelsbeing commonly used for containing beer and other liquids.

Sanding of periphery of such barrels has heretofore been effected bymachines which included a travelling sanding belt which was engaged byone of its stretches with the eriphery of the barrel for the purpose ofsmoothing or polishing the same by means of the abrasive on the outersurface of this belt. In these prior machines the sanding belt was onlycapable of moving in horizontal and vertical planes for the purpose ofengaging the belt with different parts of the barrel surface, and in theoperation of such machines he operative stretch of the sanding belt wastilted or inclined in one direction or the other relative to thesupporting pulleys for engaging the operative stretch with one or theother of the tapering ends of the barrel. This is objectionable in thatit causes an uneven strain on the sanding belt and also produces anuneven wear on the abrasive surface.

One of the objects of this invention is to so mount the sanding beltthat the same can be tilted bodily toward either side so that theoperative stretch of the belt can be tilted transversely at an anglewhich is substantially parallel with either of the tapering or inclinedends of the barrel and thus enable these inclined or tapering surfacesto be sanded, polished or smoothed without deflecting one part of thesanding belt more than another, and thus insurbelt is arrangedtransversely in a horizontal po-,

sition and is free to be tilted laterally by the operator in eitherdirection for engaging the sanding belt with a uniform pressure againsteither inclined end ofthe barrel which is to be sanded.

A further object of this invention is to so drive the sanding belt bymeans of a motor which is mounted and operatively connected with thesanding belt in such manner that the weight of the motor is utilized tokeep taut the belt which transmits the power of the motor to the sandingbelt. I

An additional object of this invention consists in the provision ofcertain improved details of construction as will hereinafter more fullyap-' pear.

In the accompanying drawings:

1933. Serial No. 660,391.

Figure 1 is a side elevation of .a barrel sanding machine embodying myimprovements.

Figure 2 is a front elevation of the same.

Figure 3 is a top plan view thereof.

Figure 4 is a fragmentary vertical longitudinal section of the frontpart of the sanding machine, taken on line 4-4 Fig. 3, on an enlargedscale.

Figure 5 is a similar view of the rear part of the machine, taken online 5-5 Fig. 3.

Figure 6 is a vertical transverse section, taken on line 6-6 Fig. 5.

Figure '7 is a fragmentary vertical longitudinal section, on an enlargedscale, taken on line 7-'7 Fig. 3.

Figure 8 is afragmentary vertical transverse section, taken on line 88Fig. 7.

Figure 9 is a hagmentary horizontal section, on an enlarged scale, ofthe rear part of the machine, taken on line 9-9 Fig. 5.

Figures 10 and 11 are fragmentary vertical sections, taken on thecorrespondingly numbered lines in Fig. 9. I

In the following description similar characters of reference indicatelike parts in the several figures of the drawings:

The numeral represents a barrel of the form which this sandingmachine'is more particularly intended to sand, smooth or polish on itsperipheral outer surface, which barrel bulges or is of large diametermidway of its length andtapers or inclines from its central or largepart toward opposite ends thereof. This barrel may be supported inposition for operation thereon by the sanding machine in any suitablemanner and the means for this purpose, which are shown in the drawingsare therefore to be merely regarded as an example of those now in commonuse.

As there shown, these holding means comprise a main frame 21 providedwith two saddles 22 upon which the barrel rests with its underside, twoclamping heads 23 engaging with opposite ends of the barrel and providedrespectively with horizontal spindles or trunnions 24, 25 which arejournaled in suitable bearings on the holder frame 21, means forrotating the barrel during the sanding operation and arresting thisrotation when the sanding operation is completed which include tight andloose pulleys 26, 27 mounted on the shaft 24, and means for moving theshaft 25 toward and from the shaft 24 for the purpose of clamping thebarrel between the heads" 3 or'releasing the same,which means include alever 28 mounted on the main frame and operatively connected with thespindle 25.

provements. includes a main frame 29 which is Iii) arranged in rear ofthe barrel holder and supembodying my improvements is mounted on theupper end of the main frame 29 and extends forwardly therefrom over thebarrel holder into a position which permits the operator to manipulatethe same while standing in front of the barrel. The preferred form ofthis sanding apparatus, as shown in the drawings, is constructed asfollows:-

On top of the main frame 29 is arranged a horizontal supporting plate ortable 30 which preferably consists of sheet metal having the form of acircular disk, and may be secured to the frame in any suitable manner soas to form an annular track or surface upon which the supports for thesanding mechanism may be rotated in a horizontal plane. Above thissupporting plate is arranged a turret 31 which is rotatable in ahorizontal plane and provided at its margin with an annular dependingflange 32 which overhangs the edge of the supporting plate 30, as bestshown in Figs. 5 and 6. This turret is of circular form and providedwith a central tubular hub 33 which turns on the vertical pivot 34projecting upwardly from the central part of the plate 30 into the hub33. The marginal part of the turret is supported at suitable intervalsby rolling members engagingthe upper side of the marginal part of theplate 30, which rolling members are preferably four in number and eachof these consisting of a roller 35 journaled in a pocket 36 on theturret and engaging its lower part with the upper surface of the plate30, as v best shown in Figs. 6, 9, 10 and 11.

Above the turret is arranged a yoke 37 which is pivotally connected withthe turret so as to be capable of rocking vertically and laterallyrelatively to the length of the machine, this being preferablyaccomplished by means of two longitudinal horizontal pivot pins ortrunnio-ns 38, each of which turns with its outer end in a bearingformed in a lug 39 projecting upwardly from a marginal part of theturret while its inner end is secured in a lug 40 depending from themarginal part of the yoke 37 and arranged adjacent to the inner side ofthe respective turret lug, 39, as best shown in Fig. 5. I

Upon this yoke is mounted a vertically swinging operating frame whichcarries the means whereby the sanding belt is movably supported so thatthe latter may be propelled and'engaged with different'parts of theperiphery of the barrel which is to be sanded. Although this operatingframe may be variously constructed the same is preferably so organizedthat the same is capable of moving bodily in a vertical plane lengthwiseof the machine for the purpose of moving the sanding belt into and outof engagement with the periphery of the barrel, also capable of movingbodily horizontally for engaging the sanding belt with different partsof the barrel throughout the length thereof, and also tilting thesanding belt transversely the .length of the machine for the purpose ofinclining the operative stretch of the sanding belt to conform with theinclination of either of the tapering ends of the barrel on oppositesides of its central bilge.

In its preferred form this operating frame is constructed as follows:

Referring more particularly to Figs. 1, 4 and 5, the numeral '77represents the rear section of the operating frame which is pivotallyconnected with the yoke 3'7 so as to be capable of swinging in avertical plane lengthwise of the machine, and a front section which isadjustably connected with the rear frame section so as to permit oftightening the sanding belt 41 which is mounted on the operating frame.The rear section of the operating frame has generally the form of arearwardly extending fork 42, the central part of which is provided witha forwardly projecting sleeve 43 and the arms of which are connected ontheir underside by a cross-piece or bridge 44 arranged between twoupright lugs 45 on the yoke 3'7 at right angles to the depending lugs40. This cross-piece 44 is pivotally connected with the lugs 45 by meansof a horizontal transverse pin 46 and is provided with a rearwardlyprojecting lug 47 to which the front end of a counterbalancing bar orarm 48 is secured. Upon the rear end of the arm 48 is mounted acounterbalancing weight 49 which may be adjusted horizontally andlengthwise of the machine toward and from the axis 46 for the purpose ofcounterbalancing the operating frame and the parts which are mountedthereon, said counterbalancing weight being provided with set screws 50for engaging the arm 48 and holding the counterbaianciw weight inposition after it is adjusted to the desired position.

The front section of the operating frame also has the general form of aforwardly extending fork 51, the rear cross bar of which is providedwith a rearwardly projecting guide tube 52 which is operativelyconnected with the rear section of the operating frame by means whichpermit this front fork to move lengthwise relative to the rear fork butprevent these parts from turning in a vertical transverse planerelatively to each other.

In the preferred construction these means include a horizontallongitudinal supporting rod 53 having the form of a tube or pipe whichis connected at its rear end with the sleeve 43 of the rear section ofthe operating frame, while the front end of this supporting bar 52extends into the sleeve 52 of the front fork of the operating frame andis connected therewith by means of a transverse pin 54 passinghorizontally through the bar or pipe 53 and projecting throughlongitudinal slots 55 in the adjacent part of the front fork tube 52, asshown by dotted lines in Fig. 5 and by full lines in Fig. 1, therebyforming a spline joint between the front and rear sections of theoperating frame which permits the front section to move lengthwiserelative to the rear section but prevents the front section from turningrelatively to the rear section.

The front section of the operating frame is also yieldingly movedforwardly relatively to the rear section by means of a spring 56surrounding the front part of the bar 53 and bearing at its front endagainst the rear end of the fork tube 52, while its rear end bearsagainst a split adjusting nut 57 which may be turned on'the screwthreaded front part of the bar 53 for obtaining the desired tension inthe spring 56, after which this nut is held against displacement bytightening the screws 58 which connect the sections thereof and pressthem against opposite sides of the bar 53.

The arms of the front fork are provided with bearings 59 in which isjournaled a transverse pulley shaft or axle 60, and on this shaft ismounted a front pulley 61 which is arrangedbetween the arms of the frontframe fork. The rear ends of the arms of the rear fork of the operatingframe are provided with bearings 62 in which are journaled the oppositeends of a rear transverse pulley shaft 53. Upon this rear shaft 63 issecured a rear sanding belt pulley 64 which is arranged-between the armsof the rear fork 42. The sanding belt 41 passes with its front and rearturns around the sanding belt pulleys 61 and 64 so as to provide a lowerlongitudinal operative stretch and an upper longitudinal return orinoperative stretch. 7

. This sanding belt may be of any. suitable and well-known constructionso as to provide a comparatively smooth inner side which runs in contactwith the supporting pulleys 61-and' 64, while its outer side is providedwith an abrasive coating of sand, emery or similar material forengagement with the periphery of the barrel which is to be sanded, andproducing a sanding, smoothing or polishing effect on the same. Thisbelt is of such a length that when applied to the pulleys 61, 64 thefront pulley 61 will be somewhat in rear of its foremost position inwhich the cross pin 54 is arranged rearwardly of the front ends of theslots 55, as shown'in Fig. 1, and the spring 56 is under tension andthereby enables the latter to exert a constant forward pressure on thefront fork for keeping the sanding belt taut and automatically taking upany slack which may occur therein.

Meansare provided for manipulating the operating frame for engaging thelower operative stretch of the sanding belt with different parts of theperiphery of the barrel and also tilting the operatingframe laterally inone direction or the other for the purpose of bringing the sanding beltin substantial parallelism with either of the inclined or tapering endportions of the barrel, these means consisting preferably of a handle orcross bar 65 mounted on the front end of one of the arms of the fork 51,as shown in Figs. 1, 2 and 3.

In order to protect the operator, who is handling the machine, frombeing injured by contact with theupper and front parts of the belt whilethe machine is in operation and also preventing injury to the operatorin case the belt should break and parts of the same fly forward,protective means are provided which preferably include a flatlongitudinal guard plate or wall 66 arranged lengthwise over the upperstretchof the sand belt, and a front wall 6'7 projecting downwardly in acurve from the front end of the top wall 67 and around the adjacent sideof the front turn of the sanding belt, as best shown in Figs. 1'7. Thisguard may be supported in any suitable manner, but in the preferredconstruction the downwardly projecting front part of this guard isconnected with one of the arms of the front fork 51 by means of abracket 68 and the longitudinal upper part of this guard is supported byangular brackets, preferably two in number, each of which has an uprightangular lower part 69 extending between thestretches of the sandingbeltand provided at its lower end witha sleeve 70 which is-secured by a setscrew 71 with the adjacent part of the supportingbar 53, and ahorizontal upper part 72 which extends from the upper endof the inclinedpart across the top of the upper guard plate 66 and is secured theretoby means of bolts '73, or any other suitable means. I

Although various means may be provided for driving the sanding belt itis preferable to employ for this, driving means which also operate aspart ofthe means for counterweighting the operating frame and the partsmounted thereon, and this form of driving mechanism, as shown in thedrawings, is constructed as follows:

The numeral '74 represents an electric motor arranged in rear of therear section of the operating frame and having its transverse shaft '75provided with a driving pulley 76 from which motion is transmitted by abelt-78 to a driven pulley '79 on one end of the rear shaft 63 of therear pulley, as best shown in Figs. 1, 2, 3, 5 and 8. This motor ismounted on a platform or base which projects rearwardly from the rearsection of the operating frame so that the weight of the motor serves asan aid to counterbalance the weight of the operating frame and the partsmounted thereon, and this platform or base is also pivotally mounted onthe rear part or section of the operating frame so that the weight ofthe motor and the platform on which it is mounted serves as a means forkeeping the driving belt 78 taut and taking out any undue slack in thesame.

In its preferred construction this motor platform includes a pair ofhorizontal longitudinal supporting bars 80 which carry the motor '74 onthe upper sides thereof and which are connected at their front ends to ahorizontal transverse rock shaft 81 which is journaled in suitable bearings 82 arranged on the rear section of the operatingframe, as bestshown in Figs. 1, 7, 8 and 9. The weight of the'motor and its platformtend constantly to turn around the axis of the shaft 81 as a centerwhich is arranged in rear of the axis of the horizontalshaft 46 whichconnects the operating frame with the yoke 37, whereby a rearward pullis constantly maintained upon the driving belt 78, so that the same iskept taut and the full power of the motor is transmitted to the sandingbelt.

In order to prevent the platform andthe mo tor from dropping too far incase of breakage of the belt 78 or while setting up the machine. formaking repairs, stop means are provided which limit the descent of themotor platform, which stop means, as shown in Figs. 7 and 9, consist ofstop fingers 83' projecting forwardly from the arms 80'of the motorplatform and adapted to engage with a stop flange 84 on the cross piece42 when the'motor and platform reach the predetermined downward limit oftheir bodily movement for tightening the belt, as shown in Fig. '7.

The electric motor is also capable of being moved lengthwise on. thearms 80' of the supporting platform for'the purpose of taking'up theslack in the driving belt, which means in the present case compriseclamping bolts 85 passing through the legs of the motor and throughlongi-. tudinal slots 86 in the arms of the motor platform. In additionto this, positive abutment means are provided on the motor platform forengagement with the motor and thereby positively hold the same againstforward motion under the pull of the motor belt. These abutment meansconsist of. horizontal abutment 1' motor rearwardly while the bolts 85are loose' the motor can be adjusted lengthwise on the platform withinthe limits of the slots 86, after which the bolts 85 may be tightenedfor holding the motor in place. After such adjustment of the motor hasbeeneffected, each of the shanks or bolts 89 is engaged with the mostavailable opening 90 in the respective platform arm and then the screw87 is turned so as to engage the'adjacent leg or front part of the motorso as to positively hold the motor in its adjusted position and preventthe latter from slipping forward if the clamping bolts are notsufficiently tight for this purpose.

Raising of the operating frame and the parts associated therewith islimited by means of a stop screw 91 arranged on the yoke 37 and adaptedto be engaged by the underside of the arm 47 which projects rearwardlyfrom the cross-piece 44 on the rear fork-shaped section'of the operatingframe, as shown in Fig. 5.

Due to the universal coupling of the operating frame with the main frameof the machine it is possible to shift the sanding belt in alldirections and thus permitting this belt to be engaged into any positionwhich enables the same to be engaged flatwise with all surfaces of abarrel, regardless of the position of the same relative to the horizon,and also enables the-sanding belt to be engaged with all parts of theperiphery of the barrel throughout the length thereof,

This universal motion is possible due to the vertical pivot 34 betweenthe main frame and the turret 31 which permits the latter to turn in ahorizontal plane, the longitudinal pivots 38 permit the yoke 37 to turnin a vertical plane crosswise of the turret, and the transverse pin 46connecting the yoke with the operating frame permits the latter to bemoved vertically.

When swinging the operating frame about the horizontal transverse pivot46 the lower operative stretch of the sanding belt may be moved towardand from the periphery of the barrel which is to be operated upon, asshown by full lines and dotted lines in Fig. 5. Upon turning theoperating frame and associated parts horizontally about the verticalpivot 34 as an axis, the sanding belt may be engaged with differentparts of the periphery of the barrel throughout the length thereof, asshown by full and dotted lines in Fig. 3, and by turning the operatingframe in a vertical plane about the longitudinal pins or trunnions 38the sanding belt may be tilted from the horizontal position shown byfull lines in Fig. 6 to the laterally tilted position shown in the samefigure, so that the lower operative stretch of the sanding belt may beengaged flatwise or in a parallel position relative to themclinedsurface which is being sanded, smoothed or polished, such as theopposite tapering ends of the barrel, thereby enabling, the entiresurface of the belt to be utilized most effectively without wearing onepart of this belt more than the other, and also without causing thisbelt to be stretched unduly at its longitudinal edge portions, butinstead insuring a uniform deflection of the sanding belt at all timesand causing the same to operate uniformly and wear longer.

Means are provided for normally holding the operating frame yieldinglyin its normal central position in which the lower or operative stretchof the sanding belt is arranged horizontally but permitting this belt tobe tilted laterally in either direction from this neutral position forengaging the same in parallelism with the inclined or tapering ends ofthe barrel. These yielding centering means, in their preferred form, asshown in Figs. 1, 2, 6 and 9, comprise two upwardly diverging centeringrods 92 which are arranged transversely above the turret and on oppositesides of the axis thereof, and each pivotally connected at its lowerendwith the adjacent part of the turret by means of a pivot pin 93 passingthrough an eye 94 at the lower end of the respecive centering rod 92 andthrough upwardly projecting lugs 95 on the adjacent part of the turret,two abutment eyes 96 arranged on the rear section of the operating frameon opposite sides of the pivot. pin 34, and each receiving the upperpart of one of the'centering rods 92, an adjusting screw nut 9'?arranged on the lower part of each of the centering rods 92, and acentering or balancing spring 98 surrounding each of the centering rods92, and bearing at its lower end against the adjusting screw 9'? and atits upper end against the inner side of the respective abutment eye 96,as best shown in Fig. 6.

The tension of thesprings 96 is so determined that when the operatingframe is free the latter will beheld in its normal central position inwhich the underside of the lower stretch of the sanding belt is arrangedhorizontally, as shown by full lines in Fig. 6, but the operator isnevertheless enabled by manual power to turn the oper-' ating framelaterally in a vertical plane, as shown partly by dotted lines in Fig.6, for the purpose of bringing the operative stretch of the sanding beltinto an inclined position in which it is sub-. stantially parallel withthe angle of the peripheral portion of the barrel which is to beoperated upon, and thus insure even engagement of the belt with thebarrel and securing uniform wear and greater durability of the belt.

It will now be apparent from the foregoing description that by the useof the universal coupling between the operating frame and the main frameof the machine the sanding belt may be shifted into any desired positionand thus enable the same to operate most effectively on the surfacewhich is to be sanded and enable this to be done economically andwithout irregular wear on the sanding belt, thereby increasing the lifeof the latter and permitting the same to do a greater amount of workbefore requiring renewal or repair.

Moreover, the various improvements in the details which have beenprovided for mounting the operating frame on the main frame,renderingthe operating frame adjustable, counterbalaneing the operatingframe, and also the means for mounting the motor and transmitting powerfrom the same to the driving belt,renders the machine as a whole compactin construction, not liable to get out of order, and enables sanding ofthe character described to be effected economically and expeditiously.

I claim as my invention:

1. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,

an operating frame upon which said pulleys are mounted, and universalcoupling means interposed between the upper side of said pedestal andthe underside of said frame whereby said operating frame is pivotallymounted on said pedestal and permitting of turning said operating framein all directions on said pedestal.

2. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,an operating frame upon which said pulleys are mounted, and universalcoupling means whereby said operating frame is pivotally mounted on saidpedestal and permitting of turning said operating frame in alldirections on said pedestal, said universal coupling means including ahorizontally lad turret, and a horizontal transverse pivot connect ingsaid operating frame with said yoke.

3. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,an operating frame upon which said pulleys are mounted, universalcoupling means whereby said operating frame is pivotally mounted on saidpedestal and permitting of turning said operating frame in alldirections on said pedestal, and spring means for yieldingly holdingsaid operatingframe in a central position relative to said turret.

4. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,an operating frame upon which said pulleys are mounted, universalcoupling means whereby said operating frame is pivotally mounted on saidpedestal and permitting of turning said operating frame in alldirections on said pedestal, said universal coupling including ahorizontal plate arranged on top of said pedestaL-a rotatable turrethaving a disk arranged above said plate and provided centrally with anupwardly projecting tubular hub and on opposite sides'of said hub withupwardly projecting lugs, a vertical pivot pin projecting upwardly fromsaid plate into said hub, a yoke arranged above said disk and havingdownwardly projecting lugs on opposite sides of its center, and upwardlyprojecting lugs arranged at right angles to said downwardly projectinglugs and on opposite sides of said operating frame, horizontal pivotpins each pivotally connecting the downwardly projecting lugs of theyoke with one of the upwardly projecting lugs of said disk, and ahorizontal pivot pin connecting said operating frame with the upwardlyprojecting lugs of said yoke.

5. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,an operating frame upon which said pulleys are mounted, universalcoupling means whereby said operating frame is pivotally mounted on saidpedestal and permitting of turning said operating frame in alldirections onsaid pedestal, said universal coupling including ahorizontal plate arranged on top of said pedestal, a rotatable turrethaving a disk arranged above said plate and provided centrally with anupwardly projecting tubular hub and on opposite sides of said hub withupwardly projecting lugs, a vertical pivot pin projecting upwardly fromsaid plate into said hub,

a yoke arranged above said disk and having,

downwardly projecting lugs on opposite sides of its center, and upwardlyprojecting lugs arranged at right angles to said downwardly projectinglugs, and on opposite sides of said operating frame, horizontal pivotpins each pivotally connecting the downwardly projecting lugs of theyoke with one of the upwardly projecting lugs of said disk, and ahorizontal pivot pin connecting said operating frame with the upwardlyproject ing lugs of said yoke, and rolling bearing members mounted onsaid disk and running on the upper side of said plate.

6. A machine for sanding barrels comprising a pedestal, a sanding beltadapted to engage the barrel to be sanded, pulleys supporting said belt,an operating frame upon which said pulleys are mounted, universalcoupling means whereby said operating frame is pivotally mounted on saidpedestal and permitting of turning said operating frame in alldirections on said pedestal, said universal coupling including a turretpivoted to turn horizontally on said pedestal and a yoke pivoted on saidturret to turn vertically about a longitudinal axis thereon and pivotedto said operating frame so that the latter turns vertically about atransverse axis relative thereon, and resilient centering means forbalancing said operating frame relatively to said turret including twoupwardly diverging centering rods pivotally conne'cted at their lowerends with said turret on opposite sides of the center of the latter,abutment eyes arranged on said operating frame on opposite sides of thelongitudinal center thereof and receiving the upper ends, respectively,of said centering rods, screw nuts arranged on said centering rods, andsprings each arranged upon one of said centering rods and engaging itsopposite ends with the screw'nut thereon and the respective abutmenteye.

'7. A barrel sanding machine comprising a ped estal, an operating framehaving its rear end pivotally mounted on said pedestal to turnvertically and projecting with its front end from one side of saidpedestal, a driving shaft jour-. naled on the rear part of said frameand having a driving pulley, sanding belt pulleys mounted respectivelyon the driving shaft and the front end of said frame, a verticallyswinging platform pivoted on said frame below said driving shaft, amotor mounted on said platform and having a motor pulley, a belt passingaround said motor pulley and said driving pulley, and stop means forlimiting the turning action of said platform under the weight of saidmotor.

8. A barrel sanding machine comprising a ped estal, an operating framehaving its rear end pivotally mounted on said pedestal to turnvertically and projecting with its front end from one side of saidpedestal, a driving shaft journaled on the rear part of said frame andhaving a driving pulley, sanding belt pulleys mounted respectively onthe driving shaft and the front end of said frame, a vertically swingingplatform pivoted on said frame below said driving shaft, a motor mountedon said platform and having a motor pulley, a belt passing around saidmotor pulley and said driving pulley, and means for adjusting said motoron said platform toward and from the axis of thelatter.

9. A barrel sanding machine comprising a pedestal, an operating framehaving its rear end pivotally mounted on said pedestal to turnvertically and projecting with its front end from one side of saidpedestal, a driving shaft journaled on the rear part of said frame andhaving a driving pulley, sanding belt pulleys mounted respectively onthe driving shaft and the front end of said frame, a vertically swingingplatform pivoted on said frame below said driving shaft, a motor mountedon said platform and having ,a motor pulley, a belt passing around saidmotor pulley and said driving pulley, and means for adjusting said motoron said platform toward and from the axis of the latter, including boltssecured to said motor and passing through longitudinal slots in saidplatform, abutment screw nuts having threaded adjusting shanks eachadapted to be secured in one or another of a lontightening screws eachworking in one of said abutment screw nuts and engaging with the innerside of said motor.

MARTIN ELSKAMP.

